1. Field of the Invention
The present invention relates to a liquid crystal display device, a polarizing plate and a backlight source.
2. Description of the Related Art
Liquid crystal display devices are in widespread use for monitors of a personal computer and a portable device and a television because of various advantages that they realize low voltage and low power consumption and they can be formed into a thinner film, downsized, or large-screen design. This liquid crystal display device has been provided in various modes according to the arrangement state of liquid crystals of a liquid crystal substance layer: for example, a TN (Twisted Nematic) mode, an IPS (In-Plane Switching) mode, an OCB (Optically Compensatory Bend) mode, a VA (Vertically Aligned: vertical orientation) mode. Especially a liquid crystal of the VA mode, of the above modes, has attracted attentions over these years because of its high contrast capability.
This liquid crystal of the VA mode, however, has an issue that the hue in the case of observing the liquid crystal from a normal direction is different from the hue in the case of observing it from a wide-angle direction in white display.
In Japanese Patent Application Laid-Open No. 2007-316156, coloring of the screen in the case of observing the liquid crystal panel obliquely is suppressed by providing an optical element which reduces the transmittance of a visible light having the wavelength of 600 nm or more supplied from a backlight source much more in the case of illuminating it obliquely than in the case of illuminating it from a light emitting surface of the liquid crystal panel in a perpendicular direction.